Gamma-aminobutyric acid receptors, commonly known as GABA receptors, are a class of receptors found in the central nervous system (CNS) that mediate the effects of the neurotransmitter gamma-aminobutyric acid (GABA). GABA receptors are an integral component of the inhibitory neurotransmitter system in the brain and play a crucial role in regulating neuronal excitability.
There are two major classes of GABA receptors: GABA-A receptors and GABA-B receptors. GABA-A receptors are ligand-gated ion channels composed of multiple subunits that form a chloride ion channel pore. Activation of GABA-A receptors by GABA leads to the influx of chloride ions into the postsynaptic neuron, resulting in neuronal hyperpolarization and subsequent inhibition of signal transmission. GABA-B receptors, on the other hand, are metabotropic receptors coupled to G-proteins, which regulate the activity of ion channels indirectly.
GABA receptors are widely distributed throughout the CNS and are found in various brain regions, including the cortex, hippocampus, and basal ganglia. They are involved in numerous physiological functions, such as regulation of anxiety and sleep, motor coordination, and memory formation. Dysfunction of GABA receptors has been implicated in several neurological and psychiatric disorders, including epilepsy, insomnia, anxiety disorders, and schizophrenia.
GABA receptors are the target of many drugs, both therapeutic and recreational, including benzodiazepines, barbiturates, and alcohol. Modulating GABA receptor activity with these drugs can have various effects, such as sedation, anxiolysis, or muscle relaxation. Understanding the functioning and regulation of GABA receptors is essential for developing new therapies targeting these receptors and improving our understanding of normal brain function.
